A semiconductor light emitting device, such as an LED (light emitting diode), includes a semiconductor layer having a light emitting layer, a p electrode, and an n electrode. In the semiconductor light emitting device, the p electrode is formed on one surface of the semiconductor layer and the n electrode is formed on the other surface of the semiconductor layer, or the p and n electrodes are formed on one surface of the semiconductor layer. In the thus configured semiconductor light emitting device, it is desired to improve the light emission efficiency.